The ''file with rules'' is a simple text file, with one '''sed''' substitution rule per line.  Invoking ''sed -f <file with rules>'' on a stream of text data is equivalent to performing '''sed''', sequentially, once for every rule in ''file with rules''.  It’s mainly a time saver, but a significant one.

The ''file with rules'' is a simple text file, with one '''sed''' substitution rule per line.  Invoking ''sed -f <file with rules>'' on a stream of text data is equivalent to performing '''sed''', sequentially, once for every rule in ''file with rules''.  It’s mainly a time saver, but a significant one.

Creating this file is another story, and is beyond the scope of this page.  The one case in your assignments where ''sed -f <file with rules>'' will be useful is precisely when transcribing the genetic code.  For this reason, a '''sed''' rules file, listing these substitutions for lowercase bases converting into uppercase amino acids, has been pre-created for you.  You’ve seen this file before: it’s ''~xmlpipedb/data/genetic-code.sed''.

Creating this file is another story, and is beyond the scope of this page.  The one case in your assignments where ''sed -f <file with rules>'' will be useful is precisely when transcribing the genetic code.  For this reason, a '''sed''' rules file, listing these substitutions for lowercase bases converting into uppercase amino acids, has been pre-created for you.  You’ve seen this file before: it’s ''~dondi/xmlpipedb/data/genetic-code.sed''.

At this point, your working directory should be ''~xmlpipedb/data''.  Thus, just typing this should allow you to look those rules over, and verify that they indeed represent the genetic code:

At this point, your working directory should be ''~dondi/xmlpipedb/data''.  Thus, just typing this should allow you to look those rules over, and verify that they indeed represent the genetic code:

  more genetic-code.sed

  more genetic-code.sed